1. Field of the Invention
The present invention relates to an exhaust control valve assembly for an engine, such as a two-cycle engine.
2. Description of the Relevant Art
In accordance with the background art, an exhaust control valve for a two-cycle engine includes a pair of valve elements. The valve elements are formed symmetrically. The valve elements sandwich a reinforcing wall, which laterally bisects a central section of an opening to a cylinder bore of an exhaust port. Such as arrangement in disclosed, for example, in Japanese Patent Laid-Open Publication No. Sho. 63-306227.
The background art's exhaust control valve suffers drawbacks. When the exhaust control valve is heated up by exhaust gases, while the engine is running, the valve element nearest to a pouch-shaped bearing hole-side tends to overheat. Overheating the valve element on this side reduces that valve element's resistance to heat, which further inclines the valve element to fail.